bulk build reuse old package for all matching dependencies?

Does anyone do bulk builds reusing old packages?
Anyone interested to setup a bulk build that keeps all old packages, only
builds new packages for version/revision changes, and always reuses old
matching packages for dependencies?
Maybe setup via cron daily so it would only do new builds of packages that
have new version/revision changes.
This would be useful to catch problems where a dependency requirement was
not changed, for example committer has new dependency installed but pkgsrc
allows old one which is not good enough.
Do any of the bulk build frameworks easily/readily support this?